APA aipamena

Østby, L. (1981). The Norwegian fertility survey, 1977: A summary of findings. International Statistical Institute ; World Fertility Survey.

Chicago Style aipamena

Østby, Lars. The Norwegian Fertility Survey, 1977: A Summary of Findings. Voorburg : London: International Statistical Institute ; World Fertility Survey, 1981.

MLA aipamena

Østby, Lars. The Norwegian Fertility Survey, 1977: A Summary of Findings. International Statistical Institute ; World Fertility Survey, 1981.